Using cloned v-fms or mouse platelet-derived growth factor receptor cDNA as a probe, we have isolated genomic DNA clones homologous to the proto-oncogene family. A novel putative kinase receptor gene has been identified and characterized by cDNA cloning. Its primary structure is similar to that of tyrosine kinase receptors thus far cloned and share a common pattern of cystreine distribution which is seen in the receptors for platelet-derived growth factor (PDGF) and colony stimulating factor (CSF-1). This new gene is overexpressed in several human sarcoma cells, suggesting that this gene may be involved in the neoplastic process of some tumors.